The Path Analysis feature augments the existing traceroute capability for more accurate, real-time visibility on equal-cost multi-path network topologies, such as the Internet.
For each hop, path analysis provides extensive information that is valuable for network analysis and troubleshooting, such as:
- IP address and reverse DNS (if available)
- Round-trip time (RTT) real-time and historical
- Color coding of the RTT value (orange if above 100 ms. and red if above 150 ms.)
- Autonomous System Number (ASN), and AS Name
- Geo-IP location with coordinates
The path analysis plot also enables the user to highlight hops based on RTT, IP, DNS, and ASN, making it easier to troubleshoot performance issues with specific nodes, as well as aggregating nodes based on ASN and DNS domains to better understand the high-level topology your users traverse to reach their destination.
Setting Up Path Analysis
There are two ways to enable path analysis: create a new target with path analysis or add path analysis to an existing target.
Create a New Target With Path Analysis
1. Navigate to the Targets tab and click Add Target.
2. On step 2 of the target setup wizard, click the Path Analysis button.
Note: It is advised to add a ping and/or HTTP test for better analysis.
3. Click the cog to expand the section and modify options. Click Save when finished.
Interval (Required): The interval between two successive runs, expressed in seconds. Must be between 60 and 3,600 seconds. The default value is 300 seconds.
Number of Flows (Required): The number of individual traceroute flows per run. Must be between 1 and 20. The default value is 20.
Source Port (Required): The source UDP port number used for the test. Must be between 1024 to 65535. The default value is 12345.
Destination Port (Required): The destination UDP port number used for the test. Must be between 1024 to 65535. The default value is 33434.
Min TTL (Required): The starting value of the Time To Live field for traceroute packets. Must be between 1 and 255. Min TTL must be less than Max TTL. The default value is 1.
Max TTL (Required): The ending value of the Time To Live field for traceroute packets. Must be between 1 and 255. Max TTL must be greater than Min TTL. The default value is 30.
Inter-packet Delay (Required): The amount of time between two consecutive packets in milliseconds. Must be between 1 and 1,000. The default value is 10.
Note: Only the Interval and Number of Flows can be edited after path analysis creation.
Add Path Analysis To an Existing Target
1. Navigate to the Targets tab and click on an existing target.
2. Click on the cog in the upper right corner and select Edit Target.
3. Under the Resources section, click the gear on the right and then click the Path Analysis button. Then click Save.
Accessing Path Analysis Results
1. Click on an agent that is associated with a target with path analysis enabled.
2. In the agent details, click on the Path Analysis tab.
1. Path Analysis Header: This section has information about the path analysis test (Source Agent, Run Interval, Concurrent Flows, Min-Max TTL). If the agent has multiple targets associated that have path analysis enabled, the path analysis test can be selected next to 'Target Destination'.
2. Path Analysis Timeline Picker: If the target has ping or HTTP enabled, you will be able to click those buttons on the right to analyze those results. If no ping or HTTP tests are enabled, alerts will be the only metric to analyze by.
If a target destination has multiple ping or HTTP tests enabled, a dropdown will appear to allow you to select other tests.
The timeline metrics can be analyzed by different time windows by clicking on the time window dropdown. Timeline options are last hour, last four hours, last day, and last week.
3. Path Analysis Run Selector: Runs that can be selected will have a blue outline. Selected runs will appear as a solid blue circle. Any runs which are unsuccessful will be a solid red circle, hovering over the red circle will give you an error message with the reason the test failed.
4. Path Analysis Graph: Path analysis results can be viewed by IP (with aggregated flows), IP (with disaggregated flows), ASN (with aggregated hops), and DNS (with aggregated hops).
Hops on the graph are able to be highlighted by using the highlight hops inputs: IP, DNS, ASN, and Round Trip Time.
Graph controls are available to maximize the path analysis graph, recenter the graph, and toggle node label visibility.